Agni is the altar-fire. Originally fire, Agni, in distinction from sun and lightning, is the fire of sacrifice; and as such is he great. One reads in v. 3. 1-2, that this Agni is Varuna, Indra; that in him are all the gods. This is, indeed, formally a late view, and can be paralleled only by a few passages of a comparatively recent period. Thus, in the late hymn i. 164. 46: "Indra, Mitra, Varuna, Agni, they say; he is the sun (the bird in the sky); that which is but one they call variously," etc. So x. 114. 5 and the late passage iii. 38. 7, have reference to various forms of Agni.
Indra had a twofold nature in producing the union of lightning and Agni; and this made him mysteriously great. But in Agni is found the first triality, which, philosophically, is interpreted as a trinity. The fire of the altar is one with the lightning, and, again, one with the sun. This is Agni's threefold birth; and all the holy character of three is exhausted in application where he is concerned. It is the highest mystery until the very end of the Vedic age. This Agni it is that is the real Agni of the Rig Veda—the new Agni; for there was probably an Agni cult (as simple fire) long before the soma cult. Indra and Agni are one, and both are called the slayers of the demons[1]. They are both united as an indissoluble pair (iii. 12, etc.). Agni, with, perhaps, the exception of Soma, is the most important god in the Rig Veda; and it is no chance that gives him the first place in each family hymn-book; for in him are found, only in more fortunate circumstances, exactly the same conditions as obtain in the case of Indra. He appealed to man as the best friend among divine beings; he was not far off, to be wondered at; if terrible, to be propitiated. He was near and kind to friends. And as he seemed to the vulgar so he appealed to the theosophy which permeates the spirit of the poets; for he is mysterious; a mediator between god and man (in carrying to heaven the offerings); a threefold unity, typical of earth, atmosphere, and heaven. From this point of view, as in the case of Indra, so in the case of Agni, only to a greater extent, it becomes impossible to interpret Agni as one element, one phenomenon. There is, when a distinction is made, an agni which is single, the altar-fire, separate from other fires; but it is seldom that Agni is not felt as the threefold one.
And now for the interpretation of the modern ritualists. The Hindu ritual had 'the three fires,' which every orthodox believer was taught to keep up. The later literature of the Hindus themselves very correctly took these three fires as types of the three forms of Agni known in the Rig Veda. But to the ritualists the historical precedence is inverted, and they would show that the whole Vedic mythological view of an Agni triad is the result of identifying Agni with the three fires of the ritual. From this crass method of interpretation it would result that all Vedic mythology was the child of the liturgy[2].
As earthly fire Agni is first ignis:[3] "Driven by the wind, he hastens through the forest with roaring tongues…. black is thy path, O bright immortal!" "He mows down, as no herd can do, the green fields; bright his tooth, and golden his beard." "He devours like a steer that one has tied up." This is common fire, divine, but not of the altar. The latter Agni is of every hymn. For instance, the first stanza of the Rig Veda: "Agni, the family priest, I worship; the divine priest of sacrifice; the oblation priest, who bestows riches," where he is invoked under the names of different priests. But Agni is even more than this; he is the fire (heat) that causes production and reproduction, visibly manifest in the sun. This dual Agni, it is to be noticed, is at times the only Agni recognized. The third form is then added, lightning, and therewith Agni is begotten of Indra, and is, therefore, one with Indra: "There is only one fire lighted in many places" (V[=a]l. 10. 2). As a poetical expression, Agni in the last form is the 'Son of Waters,' an epithet not without significance in philosophical speculation; for water, through all periods, was regarded as the material origin of the universe.
Agni is one with the sun, with lightning (and thunder), and descends into the plants.[4] To man he is house-priest and friend. It is he that has "grouped men in dwelling-places" (iii. 1. 17) like Prometheus, in whose dialectic name, Promantheus, lingers still the fire-creator, the twirling (math) sticks which make fire in the wood. He is man's guest and best friend (Mitra, iv. 1. 9; above).
An hymn or two entire will show what was Agni to the Vedic poet. In the following, the Rig Veda's first hymn, he is addressed, in the opening stanza, under the names of house-priest, the chief sacrificial priest, and the priest that pours oblations. In the second stanza he is extolled as the messenger who brings the gods to the sacrifice, himself rising up in sacrificial flames, and forming a link between earth and heaven. In a later stanza he is called the Messenger (Angiras =[Greek: aggelos]),—one of his ordinary titles:
To AGNI (i. 1).
I worship Agni; house-priest, he,
And priest divine of sacrifice,
Th' oblation priest, who giveth wealth.
Agni, by seers of old adored,
To be adored by those to-day—
May he the gods bring here to us.
Through Agni can one wealth acquire,
Prosperity from day to day,
And fame of heroes excellent.